Identification of TRPM7 channels in human intestinal interstitial cells of Cajal

Figure 1 Spontaneous electrical activity of smooth muscle cells in human colon and small intestine. A: Colonic smooth muscle cells produced slow waves with a frequency of 18.1 ± 2.1/min; B: Small intestinal smooth muscle cells also produced slow waves with a frequency of 3.1 ± 0.5/min.

Figure 2 Effects of flufenamic acid, 2-aminoethoxydiphenyl borate (2-APB) and La³⁺ on electrical responses. Flufenamic acid (50 μmo/L, A), 2-APB (50 μmo/L, B) or La³⁺ (50 μmo/L, C) were applied while recording electrical activity of isolated smooth muscles of the human colon. All drugs inhibited the spontaneous electrical activity; D: The histograms summarize the frequency of spontaneous electrical activities in human colon with flufenamic acid, 2-APB, and La³⁺. ^bP < 0.01.

Figure 3 Expression of transient receptor potential melastatin-type 7 (TRPM7) protein in human colon. Double labeling of TRPM7-like immunoreactivity (red) and c-kit–like immunoreactivity (green) within smooth muscle layers of the human colon. The mixed color yellow indicates the colocalization of both TRPM7-like and c-kit–like immunoreactivity (bar = 50 μm). DIC: differential interference contrast.

Figure 4 Expression of TRPM7 protein in human small intestine. Double labeling of TRPM7-like immunoreactivity (red) and c-kit–like immunoreactivity (green) within smooth muscle layers of human small intestine. The mixed color yellow indicates the colocalization of both TRPM7-like and c-kit–like immunoreactivity (bar = 50 μm).